Multiplying-key for adding-machines



J. H. HOPKINS.

MULTIPLYING KEY FOR ADDING MACHINES. APPLICATION FILED APR.21. 19ml 2 SHEETS-SHEET 1 Mrs/7724" Paten ted Nov. 4, 1919.

1. H. HOPKINS. MULTIPIYING KEY FOR ADDING MACHINES.

APPLICATION FILED APR.2I, I919- hmmor I (If?! HO/OAWNW 5 Mia ffo/weys order to strike the zero UNITED STATES PATENT OFFICE.

1 JOHN H. HOPKINS,

MULTIPLYING-KEY Fo-all whom it may concern:

Be it known that 1, JOHN H. llorxius, L citizen of the United States, residing at Pomona, in the county of Los Angeles and State of California, have invented new and useful Improvements in Multiplying-Keys for Adding-Machines, of which the following is a specification.

My object is to make an additional key for the purpose of simplifying the operation of multiplying upon the Dalton adding machine or any similar machine.

In order to multiply with the Dalton adding machine the number which is called the multiplicand is first placed in the machine by striking the necessary keys then the operation of multiplication, which is in reality a form of addition, is carried on by pulling the lever at the right-hand side of the machine and each operation of the lever throws the number, which has been placed in the machine as the multiplicand, once, and this operation is continued times equal to the multiplier. If the multiplier is 5 the lever is pulled five times. the multiplier is 15 the lever is operated five times for the 5, then it is necessary to strike the zero key on the machine and this adds a zero to the amount already in the machine and throws the amount over into the tens place instead of in the units place, then by pulling the lever once for the one ten of the multiplier the multiplication is complete. Striking the zero key adds another digit to the number already in the machine thereby throwing the amount in the machine into the next higher denomination.

In order' that the figures shall not be printed until the completion of'the operation, there is-a key called the non-print key, and this key is to be held down during the operation of multiplying to prevent the rinting of the figures until the operation of multiplying is complete, then the non-print key is released and the product is printed. The non-print key is held down by one of the fingers of the left hand, while another finger of the left hand holds down the repeat key all the time during the operation of multiplication, so that the amount of the multiplicand is put into the machine the number of times the lever is pulled, this stops the feed of the paper and places the product in the proper position upon the paper. In this operation of multiplying, in key with a {finger o Specification of Letters Patent.

a number of or POMONA, CALiFORNIA.

FOB- ADDING-MACHINES.

Patented Nov. 4, 1919.

Application filed April 21, 1919. Serial 1T0. 291,737.

the right hand when the left hand is performing the two jobs of holding down the non-print key and holding down the repeat key, it is necessary to take the right hand from the operating lever and strike the zero key, then reach back and grasp the handle of the operating lever and pull the lever over.

The object of my invention is to provide means for operating the zero key withthe right hand without removing the right hand from the operating lever.

Figure 1 is a perspective of an adding machine equipped with a multiplying key in accordance with the principles of my invention.

Fig. 2 is a, fragmentary detail perspective of the adding machine with parts broken away to show the multiplying key.

Fig. 3 is a top plan showing my multiplying key connected to the zero key of the adding machine.

Fig. 4 is a sectional elevation showing the details of the connection between the multiplying key and the zero key.

Referring to the drawing in detail, the bearing bracket 1 is the adding machine 3, a lever 4 is pivotally connected to the bracket 1 by a pin 5 and has a handle 6 adjacent to the operating handle '1 when the operating handle is at rest, so that when the operator grasps the operating handle 7 with his right hand and brings the handle 7 to the normal upward at rest position he may reach the handle 6 with the thumb of the right hand without removing the hand from the handle 7. A bracket 8 is fixed to the internal frame 9 of the adding machine. A rod 10 is slidingly mounted through the top 2 and through the bracket 8 in substantially vertical position, there being a pin 11 through the rod 10 to engage the bracket 8 and limit the downward moveme 't of the rod. The point 12 of the lever 4 fits loosely in a hole 13 in the upper end of the rod 10, so that the vibration of the lever 4 reciprocates the rod 10.

The lower end 14 of the rod 10 is bifurcated, a spring seat 15 is inserted downwardly upon the rod, a pin 16 is inserted through the rod to support the spring seat 15, and an expansive coil spring 17 is placed upon the rod between the spring seat 15 and the bracket 8, the tension of the spring being exerted to slide the rod downwardly until f the pin 11 strikes the bracket 8.

fixed upon the top 2 of i A pivot bracket 18 is attached to the frame 9,. a lever 19 is connected to the bracket 18 by a pin 20, said lever 19 occupying normally a horizontal position and e tending above the key levers 21. One end of the lever 19 is bent backwardly and inwardly into the plane of the rod 10 and inserted into the bifurcation of the end 14 and connected by a pin 22. The other end 23 of the lever 19 is bent downwardly to engage the lever 24 of the zero key 25. The spring 17 normally holds the end 23 elevated enough to not interfere with the operation in the usual way, and

of the zero key 25 when the handle 6 is depressed the end 23 is pressed downwardly to .operate the zero key 25 as though the button itself were manually engaged and pressed downwardly.

I have had this multiplying key applied -to a Dalton adding machine and in constant use for several months, and I find it greatly facilitates the operation of multiplying, and that after the multiplicand has been *orked out upon the key board it is not necessary to look at the machine or the key board at a all during the operation of multiplication. One hand holds the non-print key and the the other hand repeat key down while mounted in position to be peated additions,

grasps the lever handle and it is not necessary to move either hand from these positions during any amount of multiplication.

Various changes may be made without departing from the spirit of my invention as claimed.

I claim:

1. The combination with an adding machine having an operating handle and a zero key and capable of performing multiplication by repeated additions, of a hand lever reached by the thumb of the hand which grasps the operating handle and means connecting the hand lever .to the zero key so that the zero key may be operated without removing the hand from the operating handle.

2'. The combination with an addin machine having a key mechanism inclu ing a zero key and an operating handle and capable of performing multiplication by reof means for operatin the zero key with the thumb of the hand which grasps the operating handle.

In testimony whereof I have signed my name to this specification.

JOHN H. HOPKINS. 

